Usually in elevators the elevator car is generally fitted inside an elevator car sling, which the elevator car sling is suspended by hoisting roping and fitted to travel along guide rails. The guide rails are formed by connecting successive guide rail members together such that joints are formed in the assembled guide rails. These joints and possible impreciseness in guide rail alignment causes vibrations to the elevator car body via the elevator car sling connected to the elevator car body. This means that ride comfort in the elevator suffers and noise increases, which is especially the case with high speed elevators. Ride comfort for high speed elevators is very much influenced by the interface between the elevator car and the sling.
Means for damping oscillations in an elevator car is presented in U.S. Pat. No. 5,005,671 which shows an apparatus for isolating horizontal shocks, generated in high speed elevators by inaccurately aligned guide rails, from the elevator car body. The apparatus shown in U.S. Pat. No. 5,005,671 includes spherical shock absorbers for supporting the bottom side of the car body in a car sling and centering elements with cooperating guide pins connected between the top side of the car body and the upper beam of the car sling.
Problem with the prior art is that lateral vibrations caused by guide rails are formed in the upper beam of the sling and although they may be somehow dampened the upper beam may also cause some bending moment which during time will affect to the damping especially in the high speed elevators.
Another problem is that in case of high rise elevators the vibrations of the top side of the elevator car become more relevant for a large range of frequency and if they are not isolated they may induce both lateral vibrations and structure borne noise in the walls of the elevator car.